Heat transfer from separating and reattaching flows using a non-linear turbulence model

A previously proposed non-linear k-epsilon turbulence model is further examined and extended to the turbulent heat transfer prediction in the present study. The calculations are carried out for the turbulent flow and heat transfer in a sudden expansion pipe with the inlet Reynolds number of 6x10(4) and the pipe expansion ratio of 0.51. A constant heat flux through the pipe wall is specified. The calculation results are compared with the known experimental data for both momentum and thermal quantities at different downstream locations. It is shown that although the proposed model is capable of predicting the non-isotropic feature for the pipe expansion flow, it does not have significant influences on the thermal predictions. This may suggest that further modeling effort is needed for the turbulent heat transfer prediction.